Abstract: In an un-tuned state, the strings of a string instrument are excited, and a standard adjustment factor is determined for each string. When a pitch is generated as a result of a string being strummed (e.g., during normal playing of the instrument), the pitch generated by the string is adjusted by the standard adjustment factor and an intonation adjustment factor that accounts for intonation errors. An adjusted pitch is output that is in-tune and has accurate intonation.

Abstract: In an un-tuned state, the strings of a string instrument are excited, and a standard adjustment factor is determined for each string. When a pitch is generated as a result of a string being strummed (e.g., during normal playing of the instrument), the pitch generated by the string is adjusted by the standard adjustment factor and an intonation adjustment factor that accounts for intonation errors. An adjusted pitch is output that is in-tune and has accurate intonation.

Abstract: A device and method is disclosed to correct intonation errors and generate vibrato in solo instruments and vocal performances in real time. The device determines the pitch of a musical note produced by voice or instrument and shifts the pitch of that note to produce a very high quality, high fidelity output. The device includes a pitch detector that automatically recognizes the pitch of musical notes quickly. The detected pitch is then used as an input to a pitch corrector that converts the pitch of the input to an output with a desired pitch. The corrected musical note is then in tune with the pitch standard. The device and method employ a microprocessor that samples the signal from a musical instrument or voice at regular intervals using an analog-to-digital converter and then utilizes data derived from an auto-correlation function of the waveform to continuously determine the period of the waveform. The period of the waveform is then compared to a desired period or periods (such as found in a scale).